-void unmap_hugepage_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
-{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long address;
- pte_t pte;
- struct page *page;
-
- BUG_ON(start & (HPAGE_SIZE - 1));
- BUG_ON(end & (HPAGE_SIZE - 1));
-
- for (address = start; address < end; address += HPAGE_SIZE) {
- pte = ptep_get_and_clear(huge_pte_offset(mm, address));
- if (pte_none(pte))
- continue;
- page = pte_page(pte);
- put_page(page);
- }
- vx_rsspages_sub(mm, (end - start) >> PAGE_SHIFT);
- flush_tlb_range(vma, start, end);
-}
-
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
-{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
- BUG_ON(vma->vm_start & ~HPAGE_MASK);
- BUG_ON(vma->vm_end & ~HPAGE_MASK);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
-
- if (!pte_none(*pte)) {
- pmd_t *pmd = (pmd_t *) pte;
-
- page = pmd_page(*pmd);
- pmd_clear(pmd);
- mm->nr_ptes--;
- dec_page_state(nr_page_table_pages);
- page_cache_release(page);
- }
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- free_huge_page(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
-}
-